This Phase I, single center study, assessed a single intravenous rising dose of Orthoclone (OKTcdr4a) to determine the safety, tolerability, pharmacokinetics and immunologic activity in patients with rheumatoid arthritis. There were no unexpected events or side effects in conjunction with this study. A total of 18 patients were enrolled and the study ended 01-31-95. Preliminary data has been collected and analysis is proceeding.